Infographic - Trace-in Herd Tuberculosis Testing Process

Trace-in Herd Tuberculosis Testing Process

All herds that provided animals to the index herd are subject to testing.

All animals in the trace-in herd must be quarantined.

An inspector performs diagnostic screening tests.

Tuberculin is injected into the animal's skin

After 72 hours, the cattle must be re-assembled in order to read the skin test. If the skin test is negative no further testing is required. A supplemental test (usually a blood test) is done on any reactors.

A blood sample is drawn.

If the second test is positive, the test positive animals will be humanely slaughtered and tissue samples will be collected for confirmatory testing. If supplementary tests are negative the quarantine will be lifted.

Any lesions found with suspicious bacteria are tested for bovine TBDNA.

If the adult cattle test negative, the herd can be released from quarantine. Tissue samples are also culture tested. If there is a positive a new quarantine will be established.

If tissue samples from any adult cattle test positive the entire herd will be humanely depopulated. A new investigation is done to determine potential spread to other animals and herds.

All samples with or without lesions are sent for culture testing.

Samples are cultured for about 12 weeks in a CFIA laboratory. Any bacterial growth is tested for bovine TBDNA.

If all the adult cattle test negative, the herd can be released from quarantineFootnote 1.

If tissue samples from any adult cattle test positive the entire herd will be humanely depopulated. A new investigation is done to determine potential spread to other animals and herds.

Total testing time: 14+ weeks

Footnote

Footnote 1

In rare cases, a quarantine may have to be extended in order to allow for further testing because of the outcome of other herd investigations.